JP2663331B2 - How to cover the cable junction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of connecting a cable used for power transmission / distribution or telecommunications wiring to form a relay portion and recoating the relay portion. It is.

[0002]

2. Description of the Related Art Conventionally, as a configuration of a mold for coating a wire connecting portion of this kind, as shown in FIG. 3 of Japanese Utility Model Application Laid-Open No. 3-626811, both an upper mold and a lower mold are used. In some cases, a cavity is provided, and a coating having a required shape is formed by a single resin injection. However, in the mold of this shape, when the cable is for communication and the core wire is extremely thin, the core wire is bent by the pressure at the time of injecting the resin to cause eccentricity, and this core wire is exposed on the surface of the coating. And other problems.

[0003] Further, as means for coating extremely weak and easily deformable members with resin from both sides, Japanese Patent Laid-Open Publication No.
JP-A-49729 and JP-A-3-81126 disclose that when forming a casing having a symmetrical shape on the left and right sides of a lead frame, primary molding is performed with a mold in which one side of the lead frame is filled with a core. A method of forming an integrated circuit is disclosed in which the molded product obtained by performing the primary molding with the core removed is further inverted and attached to form the other side.

[0004] The drawing is provided with two surfaces, a primary molding die having cavities formed only on the upper die side, and a secondary molding die having cavities formed on both the upper die and the lower die.
First, an upper half is formed by a primary molding die, and then, the semi-finished product subjected to the primary molding is turned over to a secondary molding die (transfer), and the remaining half surface is formed. I have.

[0005]

However, Japanese Unexamined Utility Model Publication No. 3-626811 described above causes the problems described above and cannot be adopted at all.
When adopting the one disclosed in Japanese Patent Application Laid-Open No. 3-49729, first, the cables to be connected are extremely long because the connected cables are wound around a drum. The movement to the molding die does not remain, and moreover, there is a problem that the reversal required in association with the movement becomes impossible at all.

Further, when coating this kind of cable junction, a production form corresponding to a large variety and small quantity is required, and as shown in the above-mentioned Japanese Patent Application Laid-Open No. 3-49729, a transfer mold is required. What is needed inevitably raises costs and makes it impossible to respond to market demands, and solving these problems has been an issue.

[0007]

According to the present invention, as a specific means for solving the above-mentioned conventional problems, the core is exposed by peeling a resin coating between two cables at ends facing each other. In the method for coating a cable relay portion, in which a resin coating is formed again on the cable relay portion connecting the core wires, the coating method includes a first step of coating an upper half portion of the cable relay portion, and a method of coating a lower half portion. A first step having a cavity corresponding to an upper half portion of the cable relay section, and supporting the core wire of the cable relay section in a receiving groove shape from below. A step of injecting resin in combination with a first lower mold provided with a cold slug well for holding a sprue and a gate on the first lower mold side. The said The next step is to combine the upper mold with the upper half formed in the first step and the second lower mold having a cavity corresponding to the lower half of the cable junction section, It is an object of the present invention to provide a method for coating a cable relay portion, which is a step of injecting a cable.

[0008]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. In FIG. 1, reference numeral 1 denotes a cable junction. In this cable junction 1, resin coatings 3, 3 having a radius R1 are peeled off at ends where two cables 2, 2 face each other, and exposed. The core wires 4, 4 are connected by appropriate means such as welding, and an object of the present invention is to coat the cable relay portion 1 again.

FIG. 2 shows an upper mold 10 used in the coating method of the present invention in an upside-down state. The upper mold 10 has a radius corresponding to the radius R1 of the resin coatings 3, 3. r1 and a semi-circular groove 11 longer than the cable relay portion 1 is formed. When the cable relay portion 1 is fitted into the groove 11, both ends of the groove 11 are covered with the resin coating 3,
Thus, the cavity 11a is formed in the portion of the cable junction 1. A resin injection port 12 such as a sprue bush is provided at an appropriate position of the upper mold 10.

FIG. 3 shows a first lower mold 20 also used in the coating method of the present invention. This first lower mold 20 has a radius r1 corresponding to the radius R1 of the resin coatings 3, 3 at both ends. A semi-circular groove 21 is formed between the grooves 21, and a core wire having a length d equal to the length D of the cable relay portion 1 and a radius r2 corresponding to the radius R2 of the core wire 4 is formed between the grooves 21. A holding groove 22 is formed, and a cold slag well 23 having an appropriate shape such as a Z-shape or a reverse taper shape is provided at a position corresponding to the resin injection port 12 of the upper mold 10, and corresponds to the cavity 11a. In addition, a runner 24 and a gate 25 are provided.

FIG. 4 shows a second lower mold 30 which is also used in the coating method of the present invention. The second lower mold 30 is basically formed as a shape obtained by turning the upper mold 10 upside down. A groove 31 similar to the groove 11 provided in the upper mold 10 is provided, and a cavity 31a is formed when the cable relay portion 1 is fitted. The second lower mold 30 is also provided with a cold slag well 32, a runner 33, and a gate 34 in addition to the groove 31, corresponding to the cavity 31a.

Next, a method of coating the upper mold 10, the first lower mold 20, and the second lower mold 30 having the above configuration will be described. First, FIG. 5 shows a first step of the coating method according to the present invention. In the first step, the upper die 10 and the first lower die 20 are combined to perform molding.

At this time, the lower half portion of the cable relay portion 1 comes into close contact with the first lower mold 20, and the core wire 4 is held by the core wire holding groove 22.
As described above, the cavity 11a (not shown) is formed at the position of the cable relay section 1 in the upper half, and when the resin is injected from the injection port 12 in this state, the cavity 11a is formed. Is filled, and the upper half of the cable relay section 1 is formed.

FIG. 6 shows a state of a second step performed after the first step.
In the next step, the first lower mold 20 is retracted while the upper mold 10 remains in the state where the first step is performed. At this time, since the first lower mold 20 is provided with the cold slag well 23, the sprue 5 generated in the first step is attached to the first lower mold 20 side, and the injection port 12 is The resin can be injected again.

At this time, the runner 6 and the gate 7 attached to the sprue 5 are also appropriately formed, for example, a fan gate and a submarine gate, so that the runner 6 and the gate 7 adhere to the first lower mold 20 similarly to the sprue 5. In this state, it is separated from the upper mold 10, and the cable relay section 1, the upper half of which is covered, remains in the upper mold 10 as it is.

Next, the second lower mold 30 is combined with the upper mold 10 after the first lower mold 20 is retracted. Therefore, the cavity 31a is formed in the lower half of the cable junction 1 by the second lower mold 30.
Therefore, by injecting the resin in the same manner as in the first step, the lower half is covered, and the desired cable relay section 1 can be covered.

Next, the function and effect of the above-described coating method of the present invention will be described. An upper mold 10 for molding the upper half of the cable junction 1 and a pressure at the time of resin injection at this time. In a first step in which a first lower mold 20 as a work (jig) for preventing deformation of the core wire 4 is combined, a cold slug well 23 is provided in the first lower mold 20. By this, the first lower mold 20 is
When moving for the next process, sprue 5 etc.
The upper mold 10 is separated from the upper mold 10 in association with the first lower mold 20, and the injection port 12 of the upper mold 10 is made reusable.

Accordingly, the upper mold 10 can perform the second step in the first step while the first step is being performed, whereby the present invention is long and heavy. The object of the present invention is to provide a coating method which is excellent in productivity and does not require any of the above-mentioned movement, inversion and the like for the cable 2 which cannot be moved or inverted.

At the same time, the upper mold 10
The first step and the second step can be simply performed by exchanging the first lower mold 20 and the second lower mold 30, and the structure of the mold such as the transfer mold is complicated. Without this, it is possible to improve the compatibility with this kind of high-mix, low-volume production.

[0020]

As described above, according to the present invention, the coating method comprises a first step of coating the upper half of the cable junction and a second step of coating the lower half. The first step is an upper mold having a cavity corresponding to an upper half portion of the cable relay section, and a work for supporting the core wire of the cable relay section from below in a receiving groove shape to provide a predetermined position, and a sprue and A step of injecting a resin in combination with a first lower mold provided with a cold slug well for holding the gate on the first lower mold side, wherein the second step is the first step And a second lower mold having a cavity corresponding to the lower half of the cable junction section, and injecting resin by combining the upper mold with the upper half portion formed by the method described above. First, by adopting the coating method for the part This kind, there are long and weight moving relative to the non-cable such as inversion, the movement of this cable, and makes it possible provide a coating method of the inversion and the like unnecessary.

Second, the first step and the second step may simply be exchanges between the first lower mold and the second lower mold, and the mold structure such as a transfer mold becomes complicated. Without doing so, the present invention is extremely effective in improving productivity and reducing the cost of this type of method for covering a cable junction, which is a high-mix, low-volume production.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a cable relay section to be coated according to the present invention.

FIG. 2 is a perspective view showing an upper mold used for covering a cable relay portion of the present invention.

FIG. 3 is a perspective view showing a first lower mold used in the present invention.

FIG. 4 is a perspective view showing a second lower mold used in the present invention.

FIG. 5 is an explanatory view showing a first step of coating a cable relay portion according to the present invention.

FIG. 6 is an explanatory view similarly showing a second step.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cable relay part 2 ... Cable 3 ... Coating 4 ... Core wire 5 ... Sprue 6 ... Runner 7 ... Gate 10 ... Top mold 11 ... Groove 11a ... Cavity 12 ... Injection port 20 ... First lower mold 21... Groove 22... Core wire holding groove 23... Cold slug well 30... Second lower mold 31... Groove 31 a.

Claims (1)

(57) [Claims] 1. A method for coating a cable relay section, comprising peeling a resin coating of two cables at ends facing each other to expose a core wire, and forming a resin coating again on a cable relay section connecting the core wires. The coating method includes a first step of coating an upper half of the cable junction, and a second step of coating a lower half of the cable junction. The first step includes an upper half of the cable junction. An upper mold having a cavity corresponding to a portion, and a work for providing a predetermined position by supporting the core wire of the cable relay section from below in a receiving groove shape, and holding a sprue and a gate on the first lower mold side. For injecting a resin in combination with a first lower mold provided with a cold slag well for the second step, and the second step is a step in which an upper half is formed by the first step. The upper mold and the cable A method for coating a cable relay portion, comprising a step of injecting a resin in combination with a second lower mold having a cavity corresponding to a lower half portion of a cable relay portion.